I use Anki for code. Here's why Anki beats Code Cards.

Code Cards's differentiating feature is the ability to type the answer before viewing it.

But I've found it's crucial that each card be fast. Typing the answer would be way too slow.

For Ankying something like "echo $PATH | tr ':' '\n'", it's better to create multiple fill-in-the-blanks cards testing each part:

* Write $PATH on separate lines: ___ $PATH | tr ':' '\n'

* Write $PATH on separate lines: echo $PATH ___ tr ':' '\n'

* Write $PATH on separate lines: echo $PATH | ___ ':' '\n'

* Write $PATH on separate lines: echo $PATH | tr ___ '\n'

* Write $PATH on separate lines: echo $PATH | tr ':' ___

(Skip the first two if you already know "echo" and "|".)

When these cards come up you only need to spend a fraction of a second. And if you forget one part, you only need to fail that one part.

Still a nice project. Anything to increase awareness of Spaced Repetition :)